FABRIC CONDITIONING COMPOSITION

Abstract: A concentrated fabric conditioning composition comprising greater than 7 wt. % of a cationic softening agent and a zwitterionic compound of formula (I), wherein R is a C7-C27 alkyl or alkenyl group; R<1> and R<2> are independently selected from C1-14 alkyl groups; Z is O or NH; a is an integer from 0 to 1; b and c are independently selected from integers from 1 to 4; and x<-> is a compatible anion. The composition can tolerate high levels of perfume and recovers quickly to a liquid state when frozen.

Description: Fabric conditioning composition Field of the Invention The present invention relates to a fabric conditioning composition, in particular the invention relates to aqueous dispersions of fabric conditioning compositions comprising a water insoluble quaternary ammonium material and a zwitterionic compound suitable for a rinse-added fabric softener compositions. Background of the Invention Rinse added fabric conditioning composition are known. Typically such compositions contain a water insoluble quaternary ammonium fabric softening agent dispersed in water at a level of softening agent up to about 7 wt%, in which case the compositions are considered dilute, or at levels from 7 wt% to 50 wt%, in which case the compositions are known as concentrates. In US 4 137 180 (Lever Brothers Company) discloses cationic di-esters of the formula R 4 COOCH 2 R^COO wherein R-, R 2 and R 3 are each an alkyl or hydroxyalkyl group containing from 1 to 4 carbon atoms, or a benzyl group, R 4 and R 5 are each alkyl chains containing from 11 to 23 carbon atoms and X " is a water soluble anion. One of the problems associated with many fabric conditioning compositions including those containing cationic di-esters as disclosed in US 4 137 180 is the physical instability of these compounds, the problem is aggravated at high and low temperatures and by the addition of perfume. When a fabric conditioner is in concentrated form the stability issue is further exacerbated and for this reason concentrated conditioners with high levels of perfume are rarely marketed. Even when the perfume is encapsulated in a solid matrix, stability problems can occur due to leakage of the capsules. A further problem that arises in colder climates is when a fabric conditioner is transported or stored in a cold place the product gels to form a solid. In some cases the product does not recover and in others the time taken to thaw back to a liquid product frequently takes a couple of days. This poses a problem to supermarkets whom can not place the frozen product directly onto supermarket shelves. EP 280 550 and EP 507 478 (Unilever) disclose the use of selected nonionic stabilising agents to overcome the poor stability. However no mention is made of the instability of the formulation when perfume is added. US 3 984 335 (Ciko et al) discloses compositions containing a quaternised fatty amine and a fatty acid zwitterionic compound as a softening agent . Zwitterionic softening agents such as amine oxides are disclosed in EP 0 332 270 (Unilever) in combination with cationic softening agents and an amine. The problem of forming a concentrated fabric conditioner with relatively high levels of perfume is mitigated by the present invention. Furthermore the present invention aids recovery of a liquid fabric conditioner from a frozen state to a homogeneous liquid. Description of the Invention The present invention claims a fabric conditioning composition comprising greater than 7 wt% of a water insoluble cationic fabric softening agent, characterised in that the composition further comprises a zwitterionic compound of the formula: R 1 / R (COZ) a (CH 2 ) b - N + —(CH 2 ) C X- R 2 wherein R is an C 7 - 27 alkyl or alkenyl group; R 1 and R 2 are independently selected from C-. „ 4 alkyl groups; a is an integer from 0 to 1; b and c are independently selected from integers form 1 to 4; Z is oxygen or nitrogen and X is a compatible anion. At low pH's the anion may be protonated. The invention also discloses the use of an alkyl amido propyl dimethyl amino acetic acid betaine of the formula: CH 3 / R CO H(CH 2 ) 3 N + (CH 2 ) 3 COO " Na * \ CH 3 wherein R is a C n . 17 alkyl chain or mixtures thereof, to stabilise a perfumed fabric conditioner or to form a concentrated fabric conditioner. The cationic active used in the present invention preferably comprises a water insoluble cationic fabric softening agent comprising a biodegradable quaternary ammonium material with at least one ester link. Preferred materials are water insoluble cationic fabric softening agents comprising a compound having two C12-28 alkyl or alkenyl groups connected to a quaternary nitrogen via an ester link. Of particular interest with the present invention are softening compounds having the formula: in which R 1 is a . -Q.^ alkyl groups, R 2 and R 3 are the same or different C 12 - C 22 alkyl or alkenyl groups and T is the same or different -C-0 or -O-C- or -O-C-0 groups and X " is a water soluble II II II o o o anion It is especially preferred if the quaternary ammonium material is of the formula R-COO wherein R- . R 2 and R 3 are each an alkyl or hydroxyalkyl group containing from 1 to 4 carbon atoms, or an alkenyl with 2 to 4 carbon atoms, or a benzyl group, R 4 and R 5 are each alkyl chains containing from 8 to 28 carbon atoms and X " is a water soluble anion. It is further preferred if the water insoluble cationic active is N, -dihardened(tallowoyl-oxy) N,N-trimethyl ammoniopropane chloride Preferred materials and their method of preparation are described in US 4 137 180 (Lever Brothers) . Preferably these materials comprise small amounts of the corresponding mono- ester as described in US 4 137 180 for example 1-tallow, 2- hydroxytrimethyl ammonium propane chloride. The level of ester linked ammonium compound is above 7 % by weight of the composition; more preferably above 15% by weight of the composition; most preferably from 15% to 40% by weight of the composition. It is advantageous if the zwitterionic material used in the present invention is an alkyl amido propyl dimethyl amino acetic acid betaine of the formula: CH 3 R CONH(CH, JXT (CH 2 )-, COO " Na * \ CH 3 wherein R is a C - 17 alkyl chain or mixtures thereof. The level of zwitterionic material is preferably from 0.1 wt% to 8 wt% of the composition; more preferably from 0.4 wt% to 5 wt% of the total composition. The fabric conditioning composition may be formed from any base but it is especially preferred if the base is aqueous. The composition may also contain long chain fatty acid material for example C 8 - C 24 alkyl or alkenyl monocarboxylic acids or polymers thereof. Preferably saturated fatty acids are used, in particular hardened tallow C 16 - C 18 fatty acids. Preferably the fatty acid is non-saponified, more preferably the fatty acid is free for example oleic acid, lauric acid or tallow fatty acid. The level of fatty acid material is preferably more than 0.1%, more preferably more than 0.2% by weight. Especially preferred are dilutes in which the fatty acid material is present from 0.25 wt% to 20 wt%.. The weight ratio of quaternary ammonium compound to fatty acid material is preferably from 1:10 to 10:1. The composition can also contain one or more optional ingredients, selected from the group consisting of non- aqueous solvents, pH buffering agents, perfumes, perfume carriers, inorganic salts, fluorescers, colorants, hydrotopes, antifoaming agents, antiredeposition agents, enzymes, optical brighteners, opacifiers, antishrinking agents, drape imparting agents, antistatic agents and ironing aids and concentrating agents such as glycerol monostearate. It is also preferable if ethoxylated fatty alcohols are present in the composition. It is especially advantageous if they are present from 0.5 wt% to 2 wt% of the total composition. The perfume may be encapsulated or free. The level of perfume in the product is preferably above 0.1 wt%, more preferably between 0.5wt% and 3.0 wt%. The composition may also contain nonionic fabric softening agents such as lanolin and derivatives thereof. It is desirable if the viscosities of these fabric compositions lie in the range from 15 mPa.s to 120 mPa.s at a shear rate of 110s "1 . The compositions of the invention preferably have a pH of more than 2, more preferably between 2 and 5. The invention will now be illustrated by the following non- limiting examples. EXAMPLES In the examples all percentages are expressed by weight. Comparative examples are represented by a letter while examples of the invention are represented by a number. Preparation of Fabric Conditioning Composition Liquid fabric softening agents were made up as follows: The cationic fabric softening agent and nonionic stabilising agent were premixed and heated together to form a clear melt . The molten mixture thus formed was added over a period of at least one minute to water at ambient temperature with constant stirring to form a dispersion. Perfume was added to the aqueous mixture. Addition of the zwitterionic material occurred either a) to the molten melt b) to the aqueous mixture prior to or with the addition of the perfume. HT TMAPC is 1,2 dihardened tallowyloxy trimethyl ammoniopropane chloride ex Hoescht. Tego betaine L is Alkyl amido propyl dimethyl amino acetic acid betaine ex Shell. The Examples were prepared according to method a) or b) above. Examples A, B, E and F flocculated within 12 hours at ambient temperature Examples 1, 2, 5 and 6 remained stable for several months at ambient temperature. Storage results for Exmaples 3, 4, C and D were as follows Table 2 Example Time taken for flocculation to occur. 37°C 45°C 20°C 3 6 months 2 weeks > 6 months C 4 weeks 1 day 3 months 4 4 months 2 weeks > 6 months D 4 weeks 1 day 3 months Examples 7 and G Table 3 Example wt% Composition 7 G HT TMPAC 24 24 Tego betaine 0.6 - Perfume 0.8 0.4 Tallow alcohol 1.0 1.0 Calcium chloride 0.2 0.2 Water to 100 wt% Both Example 7 and Example G flocculated on addition of perfume. However Example 7 needed twice as much perfume to flocculate as Example G. Example 8 and H Table 4 Composition % wt Example 8 Example H Dihardened tallow dimethyl ammonium 10.8 10.8 chloride Dihardened tallow fatty acid 2.7 2.7 Ethylene glycol 9.0 9.0 Tallow alcohol 35 EO 1.0 1.0 Tego betaine 0.6 - Water -- to 100 -- Examples l to 4, 7, 8, A to D, G and H were frozen, Examples 1 to 4 and example 7 recovered from freezing within 1 to 2 hours. Examples A to D and example recovered from freezing within 2 to 4 days . Example 8 recovered from freezing within 1 hour. Example H recovered from freezing within 4 hours. It is thus demonstrated that the presence of a zwitterionic material aids recovery from freezing. The recovery from freezing is most enhanced with materials containing an ester link. Example I Table 5 Composition % wt Example I HT TMPAC 24 lauryldimethyl amine oxide 1 Perfume 0.5 Tallow alcohol 35EO 1.0 Calcium chloride 0.2 Water to 100 wt% Example I was prepared according to method a or b. Flocculation occurred within 1 week at room temperature no matter what method or preparation was used. It is thus shown that not all amphoteric compounds are suitable for use with this invention.

Claims: Claims 1) A fabric conditioning composition comprising greater than 7 wt% of a cationic softening agent, characterise in that the composition further comprises a zwitterion compound of the formula: R 1 I R (COZ) a (CH,) b _N + _(CH,) c _χ- I R 2 wherein R is an C 7 - 27 alkyl or alkenyl group; R 1 and R 2 are independently selected from C _ 4 alkyl groups; a is an integer from 0 to 1; b and c are independently selected from integers from 1 to 4; and X is a compatible anion. 2) A fabric softening agent according to claim 1 in which the cationic softening agent is a biodegradable quaternary ammonium material with at least one ester link. 3) A fabric conditioning composition according to Claim 2 in which the water insoluble cationic fabric softening agent comprises a compound having two C12-28 alkyl or alkenyl groups connected to a quaternary nitrogen via ester link. 4) A Fabric conditioning composition according to Claim 3 in which the water insoluble cationic fabric softening agent is of the formula: R„COOCH-, R 5 COO wherein R-, R 2 and R 3 are each an alkyl or hydroxyalkyl group containing from 1 to 4 carbon atoms, or an alkenyl with 2 to 4 carbon atoms, or a benzyl group, R 4 and R 5 are each alkyl chains containing from 8 to 28 carbon atoms and X " is a water soluble anion. 5) A fabric conditioning composition according to any preceding claim in which the zwitterionic material is an alkyl amido propyl dimethyl amino acetic acid betaine of the formula: CH, / R CONH(CH 2 ) 3 N + (CH 2 ) 3 COO " Na + \ CH, wherein R is a C u . 17 alkyl chain or mixtures thereof, 6) A fabric conditioning composition according to any preceding claim in which the level of zwitterionic material is from 0.1 wt% to 8 wt% 7) A fabric conditioning composition according to claim 5 in which the level of zwitterionic material is from 0.4 wt% to 5 wt% 8) A fabric conditioner according to any preceding claim which comprises an aqueous base. 9) A composition according to any preceding claim which further comprises a fatty acid. 10) Use of an alkyl amido propyl dimethyl amino acetic acid betaine of the formula: CH, / R CONHCCH,)-, N + (CH 2 ) 3 COO " Na + I CH 3 wherein R is a C π - 17 alkyl chain or mixtures thereof, to stabilise a perfumed fabric conditioner. 11) Use of an alkyl amido propyl dimethyl amino acetic acid betaine of the formula: CH, / R CONH(CH 2 ) 3 N * (CH 2 ) 3 COO " Na * CH, wherein R is a C n . 17 alkyl chain or mixtures thereof, to form a concentrated fabric conditioner.

Inventors: FRASER STUART BERNARD, NEILLIE WILLIAM FREDERICK SOUT, NESS JEREMY NICHOLAS, THORPE JACQUELINE MARIE, FRASER, STUART, BERNARD, NEILLIE, WILLIAM, FREDERICK, SOUTAR, NESS, JEREMY, NICHOLAS, THORPE, JACQUELINE, MARIE
Applicants: UNILEVER NV, UNILEVER PLC, UNILEVER N.V.
Application year: 1994
Main classification: C11D3
IPC codes: C11D1, C11D3, D06M13